This invention relates to a ground circuit voltage detector for monitoring stray ground voltages occurring in a dairy parlor and for providing an instantaneous warning indication whenever the stray voltage reaches a first level and a sustained alarm indication if the stray ground voltage reaches a second level.
Dairy farms have increasingly employed electrical systems to control milking operations. These electrical systems are typically serviced by a single phase power distribution system having two 120 volt lines and a common neutral conductor to provide both 120 volt and 240 volt service. Any imbalance between the loads on the two 120 volt lines will result in circulating currents in the neutral conductor developing stray neutral-to-ground voltages which may affect the cows.
Stray ground voltages may also be developed in dairy parlor equipment such as a water trough, a stall or a stanchion pipe. Where a cow is likely to come in contact with such equipment it is necessary to monitor the ground voltages developed therein.
Dairy cows are extremely sensitive to electrical voltages. When subjected to an electric voltage, the cows may not milk out completely, become nervous, reluctant to drink and reluctant to even enter the dairy parlor or barn. Further, stray electrical voltages are believed by some to cause an increase in the incidence of mastitis and to lower milk production. The adverse effects on the dairy herd can result in serious economic loss to a dairy farmer.
Known voltage detectors have been found inadequate in monitoring stray voltages developed in the dairy parlor equipment. The known voltage detectors are complex, costly, and require continuous supervision to determine the occurrence of excessive stray ground voltages.